Prediction of acoustic radiation from axisymmetric surfaces with arbitrary boundary conditions using the boundary element method on a distributed computing system

This paper presents a computational technique using the boundary element method for prediction ofradiated acoustic waves from axisymmetric surfaces with nonaxisymmetric boundary conditions.The aim is to predict the far-field behavior of underwater acoustic transducers based on theirmeasured behavior in the near-field. The technique is valid for all wavenumbers and uses a volumeintegral method to calculate the singular integrals required by the boundary element formulation.The technique has been implemented on a distributed computing system to take advantage of itsparallel nature, which has led to significant reductions in the time required to generate results.Measurement data generated by a pair of free-flooding underwater acoustic transducersencapsulated in a polyurethane polymer have been used to validate the technique againstexperiment. The dimensions of the outer surface of the transducers including the polymer coatingwere an outer diameter of 98 mm with an 18 mm wall thickness and a length of 92 mm. Thetransducers were mounted coaxially, giving an overall length of 185 mm. The cylinders hadresonance frequencies at 13.9 and 27.5 kHz, and the data were gathered at these frequencies